This project previously established a model system to study the effects of killer lymphocytes on foreign cell membranes by using antibody coated lipid bilayers as target membrane for attack by normal human lymphocytes. This project is being extended in two ways. First, Dr. Stephens has set up the apparatus for intracellular electrical recording of target cells, so that the membrane events of immune lytic mechanisms can be studied directly. Second, antigenic liposomes have been prepared, and the release of fluorescent dye used to follow the action of antibody-mediated lymphocyte attack on these membranes. Preliminary results indicate that killing conditions do give rise to marker release from the liposomes. BIBLIOGRAPHIC REFERENCE: Blumenthal, R., Weinstein, J.N., and Henkart, P.: Lipid model membrane studies on immune cytotoxic mechanisms. In Miller, M.W., and Shamoo, A.E. (Eds.): Proceedings of the 9th Rochester International Conference on Environmental Toxicity-Membrane Toxicity. New York, Plenum Press, 1977.